With the rise of antibiotics resistance worldwide, it is necessary to develop new antibacterial agents with new mechanisms for killing the emerging antibiotic-resistant bacteria. FtsZ is a new promising target for new antibiotics, which forms a Z-ring and then further regulates bacterial cell division. Here with analysis of the structure-activity relationship of PC190723, this research aims to develop a novel class of benzamide-skeleton compounds which can inhibit FtsZ protein and kill bacteria, and to optimize their pharmacokinetics for the discovery of a drug candidate that can enter clinical trial.Continue reading
Herein we report a ruthenium catalyzed regioselective allylic C—H amidation. By employing [Ru(cymene)Cl2]2 as catalyst, C—H activation and nitrene insertion are sequentially perform, followed by a reductive elimination, selectively construct a C—N bond on branch position in metal pi-allyl intermediate. Nitrene precursors such as sulfonylazide and dioxazolone are successfully insert to both activated and non-activated olefin. This strategy provides a simple, cheap method for constructing C—N bond on simple olefin, which potentially useful in late stage functionalization.Continue reading
Diaryl thioethers are usually synthesized from thiols in which industrial-scale use is discouraged by the repulsive odor and toxicity. A scalable reaction protocol for diaryl thioether synthesis using sodium arylsulfinates and iodoarenes is presented. Upon the presence of copper or palladium catalysts and DABCO, thioethers can be synthesized in moderate to good yield with broad substrate scope. The mechanistic study showed that radical process was involved, while DABCO-N-oxide radical can be identified by HRMS analysis. A plausible mechanism suggests a synergistic reduction of sulfinate by Cu(II) and DABCO, followed by cross-coupling with aryl iodide to afford the desired product.Continue reading
This poster includes the background of this study and the major results.
The major part of this study focuses on Pd-catalyzed highly sterically hindered cross-coupling reaction between enol carbamates and Grignard reagents, which is presented for the first time. Broad scope of alkenes was synthesized with high stereoselectivity. Furthermore, the successful synthesis of Tamoxifen is achieved by this strategy.
Defect and phase engineering can effectively tune the activity of photocatalysts by altering their band structure and active site configuration. Herein, we report the crystal phase-controlled synthesis of tungsten oxide (WO3) nanoplates by wet chemical approach. By adjusting the ratio of trioctylphosphine and trioctylphosphine oxide, oxygen vacancies are induced in WO3 accompanying the crystal structure transition from monoclinic to orthorhombic and pseudo-cubic phase. The experimental results and DFT calculations reveal that the increased oxygen vacant sites in WO3 leads to the upshift in both conduction band minimum and valence band maximum. The reformed band structure of reduced WO3 samples (WO3−x) enables the photocatalytic HER without the assistance of co-catalyst to achieve a maximum rate of 340 μmol g−1 h−1.Continue reading
2D porous non-layered MoNx/Mo/CoMoy heterostructures have been fabricated by using 2D layered cobalt doped ZnMo layered nanosheets as the starting materials. The 2D morphology is well remained after heat treatment of the precursors in reducing atmosphere. The intrinsic activity is improved by constructing the heterostructures, which exhibit higher HER activity than that of their single-phase counterparts.Continue reading
Cellulose was found to undergo autocatalytic hydrolysis in water with presence of salt using microwave irradiation as heating source1. Wood-based waste contain great amount of cellulose which may also undergo autocatalytic hydrolysis for bio-fuel production. Herein, we discover that the yield of polysaccharides hydrolysis with the presence of salt increases approximately 120 to 250% at 190 oC from different wood-based waste. Moreover, solid residue after hydrolysis can undergo hydrolysis again to increase the total yield. However, the yield is relatively low (approximately 1%) due to temperature limitation of the instrument.Continue reading
High water content in crude bioethanol deters the efficient catalytic production of biodiesel via transesterification. Manganese glycerolate (MnGly) was explored as water-tolerant heterogeneous catalysts towards biodiesel production, withstanding the presence of 80 wt.% water in ethanol for over 90% conversion. The application of the catalysts in utilizing commercially available crude bioethanol in the presence of 14.1 wt% of ethanol and 10 wt.% of glucose was confirmed to exhibit nearly 90% conversion in 24 hours. The results open up the possibility to simplify the current complicated and energy-intensive purification steps of bioethanol on biodiesel application, ultimately achieving a more sustainable process.Continue reading
Differential adsorption behaviour of L- and D-Lys over H-ZSM-5 has been observed experimentally by circular dichroism (CD) spectroscopy and thermogravimetric analyses (TGA). The fundamental reason is explained by the structural study based on the Rietveld refinement of the high-resolution synchrotron X-ray powder diffraction (SXRD) data and the density functional theory (DFT) calculation.Continue reading